Major cause of dementia discovered

An international team of scientists has confirmed the discovery of a major cause of dementia, with important implications for possible treatment and diagnosis.

Professor Garth Cooper from The University of Manchester, UK, who leads the Manchester team, says the build-up of urea in the brain to toxic levels can cause brain damage – and eventually dementia.

The work follows Cooper’s earlier studies which identified metabolic links between Huntington’s other neurodegenerative diseases, as well as Type-2 diabetes (T2D).

Other members of the team include the University of Auckland and AgResearch, New Zealand; the South Australian Research and Development Institute, Australia; and Massachusetts General Hospital and Harvard University, US.

The 2016 study revealing that urea is similarly linked to Alzheimer’s shows that the discovery could be relevant to all types of age-related dementias.

The Huntington’s study also showed that the high urea levels occurred before dementia set in, which could help doctors to diagnose and treat dementia.

Cooper said: “This study on Huntington’s disease is the final piece of the jigsaw which leads us to conclude that high brain urea plays a pivotal role in dementia. More research, however, is needed to discover the source of the elevated urea … particularly concerning the potential involvement of ammonia and a systemic metabolic defect.

“This could have profound implications for our fundamental understanding of the molecular basis of dementia, and its treatability, including the potential use of therapies already in use for disorders with systemic urea phenotypes.”

Dementia results in a progressive and irreversible loss of nerve cells and brain functioning, causing loss of memory and cognitive impairments, affecting the ability to learn.

Currently, there is no cure.

The team used human brains, donated by families for medical research, as well as transgenic sheep in Australia.